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11.
目的:通过检测正常人群、梅毒未治疗患者、梅毒治疗后非梅毒螺旋体抗原血清试验转阴患者和梅毒血清固定患者血清IL-10、IL-12水平,并对梅毒血清固定患者血清IL-10和IL-12作相关性分析。以探讨细胞免疫与梅毒血清固定的关系,为有效治疗梅毒血清固定患者提供一定的理论依据。方法:采用双抗体夹心ELISA法分别检测正常人群组、梅毒未治疗组、梅毒治疗转阴组和梅毒血清固定组的IL-10和IL-12水平,将各组IL-10和IL-12水平行统计学分析。对梅毒血清固定组中IL-10与IL-12作相关性分析。结果:梅毒血清固定组患者IL-10水平显著高于正常对照组(P<0.01)、治疗后阴转组(P<0.01)及梅毒未治疗组(P<0.05);梅毒血清固定组患者IL-12水平与正常对照组、治疗后阴转组及梅毒未治疗组之间差异无显著性(P>0.05);梅毒血清固定组患者IL-10与IL-12水平之间无明显相关性(r=0.417,P>0.05)。结论:梅毒血清固定组患者机体内细胞免疫受到一定程度的抑制,发生了免疫不平衡,这种免疫抑制和不平衡可能造成了梅毒螺旋体能够逃脱机体的免疫监视而残存,成为引起血清固定的原因之一。 相似文献
12.
SQA鳌合盐的急性毒性和致突变性研究 总被引:2,自引:0,他引:2
目的 检测稀土壳糖胺(SQA)鳌合盐的急性毒性和致突变性。方法 采用霍恩氏法进行急性经口毒性试验,采用小鼠骨髓嗜多染红细胞微核试验、小鼠精子畸形试验和Ames试验对受试物进行致突变性研究。结果 SQA鳌合盐的经口LD50>10000mg/kg体重;小鼠骨髓嗜多染红细胞微核试验显示无诱发微核作用,小鼠精子畸形试验未见精于畸形率增高,Ames试验在加和不加S9条件下均无致突变性。结论 SQA鳌合盐属实际无毒级物质,在该实验条件下,无致突变作用。 相似文献
13.
目的研究青藏高原鼠疫耶尔森菌(鼠疫菌)基因组型分布特征.方法对分离到的青藏高原鼠疫菌297株,根据已经证实的22个差异区段设计引物,每株鼠疫菌的每个基因差异区段都采用PCR技术进行验证.结果在喜马拉雅旱獭鼠疫自然疫源地中,鼠疫菌基因组型有9种,分别为1、5、6、7、8、10、11、新基因组型和Ype-ancestor型,其中以5、8和10型为主,3种基因组型合计所占比例为80.6%(204/253),而且不同地区鼠疫菌基因组型的分布也不一致.青藏高原青海田鼠鼠疫疫源地鼠疫菌基因组型全部为14型.结论青藏高原鼠疫菌基因组型分布具有明显的地理特征.根据基因组型的分布状况推测出了鼠疫菌在青藏高原的传播路径. 相似文献
14.
Sustained, retransplantable, multilineage engraftment of highly purified adult human bone marrow stem cells in vivo 总被引:4,自引:8,他引:4
Civin CI; Almeida-Porada G; Lee MJ; Olweus J; Terstappen LW; Zanjani ED 《Blood》1996,88(11):4102-4109
Data from many laboratory and clinical investigations indicate that CD34+ cells comprise approximately 1% of human bone marrow (BM) mononuclear cells, including the progenitor cells of all the lymphohematopoietic lineages and lymphohematopoietic stem cells (stem cells). Because stem cells are an important but rare cell type in the CD34+ cell population, investigators have subdivided the CD34+ cell population to further enrich stem cells. The CD34+/CD38- cell subset comprises less than 10% of human CD34+ adult BM cells (equivalent to < 0.1% of marrow mononuclear cells), lacks lineage (lin) antigens, contains cells with in vitro replating capacity, and is predicted to be highly enriched for stem cells. The present investigation tested whether the CD34+/CD38- subset of adult human marrow generates human hematopoiesis after transfer to preimmune fetal sheep. CD34+/ CD38- cells purified from marrow using immunomagnetic microspheres or fluorescence-activated cell sorting generated easily detectable, long- term, multilineage human hematopoiesis in the human-fetal sheep in vivo model. In contrast, transfer of CD34+/CD38+ cells to preimmune fetal sheep generated only short-term human hematopoiesis, possibly suggesting that the CD34+/CD38+ cell population contains relatively early multipotent hematopoletic progenitor cells, but not stem cells. This work extends the prior in vitro evidence that the earliest cells in fetal and adult human marrow lack CD38 expression. In summary, the CD34+/ CD38- cell population has a high capacity for long-term multilineage hematopoietic engraftment, suggesting the presence of stem cells in this minor adult human marrow cell subset. 相似文献
15.
Radiofrequency catheter ablation of septal accessory pathways in the pediatric age group 总被引:3,自引:0,他引:3
Mandapati R Berul CI Triedman JK Alexander ME Walsh EP 《The American journal of cardiology》2003,92(8):947-950
Radiofrequency catheter ablation (RCA) of septal accessory pathways may be technically challenging in children due to the risk of inadvertent atrioventricular (AV) block in the setting of small cardiac dimensions. Outcomes were reviewed for all patients aged < or =19 years with manifest and concealed septal accessory pathways undergoing RCA since 1990 at a single institution. One hundred forty-five procedures were performed in 127 patients (mean age 11.6 years). The number of studies according to accessory pathway location were: anteroseptal (n = 36), midseptal (n = 20), mouth of coronary sinus (n = 40), middle cardiac vein (n = 6), right posteroseptal (n = 21), and left posteroseptal (n = 22). Ablation was deferred for 9 patients (6 anteroseptal and 3 midseptal) in favor of additional pharmacologic trials. Acute success rates for targeted accessory pathways were: anteroseptal (96%), midseptal (94%), mouth of coronary sinus (88%), middle cardiac vein (100%), right posteroseptal (100%), and left posteroseptal (96%). Recurrence rates during follow-up were: anteroseptal (14%), midseptal (12%), mouth of coronary sinus (3%), right posteroseptal (4%), and left posteroseptal (4%). Permanent second or third degree AV block occurred in 4 of 136 RCA attempts (3%), involving 2 anteroseptal and 2 midseptal pathways. In 3 of these 4 cases, a high probability of block was anticipated from prior ablation efforts, prompting pacemaker insertion before or in conjunction with RCA. Thus, in the pediatric age group, acute RCA success rates for septal accessory pathways can exceed 90%. The risks of AV block and accessory pathway recurrence are most relevant to anteroseptal and midseptal pathways. These data may be factored into patient selection and the decision whether to ablate. 相似文献
16.
Stephenson EA Collins KK Dubin AM Epstein MR Hamilton RM Kertesz NJ Alexander ME Cecchin F Triedman JK Walsh EP Berul CI 《Journal of cardiovascular electrophysiology》2002,13(10):1009-1014
INTRODUCTION: Recent studies in adult populations have revealed seasonal variation in the frequency of acute cardiovascular events, including life-threatening arrhythmias, demonstrating increased events during winter and early spring. Trends in the time of day that arrhythmias occur also were noted. We sought to establish whether pediatric and young adult congenital heart disease implantable cardioverter defibrillator (ICD) recipients have circadian or seasonal variability in shock frequency, similar to adult populations. METHODS AND RESULTS: Data from ICD patients at six pediatric centers in North America were analyzed to assess the timing of life-threatening arrhythmias. The populations consisted of children and adults with congenital heart disease and ICDs placed for malignant arrhythmias. Data were considered in 46 patients who received appropriate therapy (total 139 episodes) for ventricular tachycardia or ventricular fibrillation. Multiple variables were analyzed, including time of day, day of week, and month of year. In contrast to previously studied adult patients, fewer events occurred in the early morning (7.5%), with the most therapies occurring between 6 P.M. and midnight (35%). An increased frequency of therapies was observed in the fall and winter (September-January), representing 60% of all appropriate shocks. Unlike adult populations, Mondays did not have an increased frequency of malignant arrhythmias. CONCLUSION: Pediatric and adult congenital heart disease populations have moderate seasonal and 24-hour variation in ICD event rate, with some distinctly different peaks than those seen in typical adult ICD populations. These findings suggest circadian variation in arrhythmia vulnerability that may differ from conventional occupational, physical, or emotional stressors. (J Cardiovasc Electrophysiol, Vol. 13, pp. 相似文献
17.
目的:分析老年退行性心脏瓣膜病(SDHVD)与多器官疾病的发生状况。方法老年人3896例,男2884例,女1012例,年龄60~103(78±13)岁。所有研究对象均进行心脏彩超、体检、相关辅助检查,并对多器官疾病进行分析。结果3896例患者中,SDHVD1225例(31.4%),无SDHVD2671例(68.6%),SDHVD组与对照组多器官疾病的发病率分别为高血压病49.3%vs 28.4%,冠心病38.5%vs23.8%,心力衰竭36.2%vs 17.3%,肺心病6.3%vs 3.1%,脑卒中21.6%vs 9.6%,肾功能不全6.9%vs 3.2%,胃食管反流病21.3%vs 10.3%,两组比较差异均有统计学意义(P<0.05),而糖尿病为11.2%vs 12.1%,两组比较差异无统计学意义(P>0.05)。结论 SDHVD组多器官疾病显著增高,可能由于SDHVD心脏重构改变,血流动力学异常,促发了多器官疾病的发生。 相似文献
18.
Rachel Lampert Brian Olshansky Hein Heidbuchel Christine Lawless Elizabeth Saarel Michael Ackerman Hugh Calkins Mark Estes Mark Link Barry Maron Frank Marcus Melvin Scheinman Bruce Wilkoff Douglas Zipes Charles Berul Alan Cheng Ian Law Michelle Loomis Cheryl Barth Cynthia Brandt David Cannom 《Heart rhythm》2012,9(9):1577-1578
19.
20.
目的评价鼻中隔偏曲矫正术对持续性变应性鼻炎(allergicrhinitis,AR)伴鼻中隔偏曲患者症状和生活质量的影响。方法应用症状视觉模拟评分量表(Visual Analogue Scale,VAs)和鼻结膜炎生存质量量表(Rhinocon junctivitis Quality of Life Questionnaire,RQI。Q)对62例持续性变应性鼻炎伴鼻中隔偏曲患者行鼻中隔偏曲术前、术后1个月、术后6个月临床症状和生活质量进行研究。结果鼻中隔偏曲矫正术后1个月、6个月患者症状、生活质量较术前均得到改善。术后1个月、6个月RQI.Q量表中各个维度的得分较术前明显降低,差异有统计学意义(P〈0.05);术后6个月除总评分外,其余各维度与术后1个月比较,差异无统计学意义(P〉0.05)。VAS量表显示:术后患者症状较术前均有不同程度的改善,但改善最明显的为鼻塞,其次为打喷嚏。结论变应性鼻炎伴鼻中隔偏曲患者的生活质量降低,鼻中隔偏曲矫正术能明显的改善患者症状同时能提高患者的生活质量。 相似文献